diff --git a/packages/pwa-kit-runtime/CHANGELOG.md b/packages/pwa-kit-runtime/CHANGELOG.md
index 80108aa019..59833e2cdd 100644
--- a/packages/pwa-kit-runtime/CHANGELOG.md
+++ b/packages/pwa-kit-runtime/CHANGELOG.md
@@ -1,4 +1,5 @@
 ## v3.16.0-preview.1 (Feb 09, 2026)
+- Updated the SLAS private client proxy to enable customizing the proxy response body [#3662] https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3662/
 
 ## v3.16.0-preview.0 (Feb 06, 2026)
 - Migrate AWS SDK from v2 to v3 [#3566](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3566)
diff --git a/packages/pwa-kit-runtime/src/ssr/server/build-remote-server.js b/packages/pwa-kit-runtime/src/ssr/server/build-remote-server.js
index 22c76c4b1f..5c4585b4f6 100644
--- a/packages/pwa-kit-runtime/src/ssr/server/build-remote-server.js
+++ b/packages/pwa-kit-runtime/src/ssr/server/build-remote-server.js
@@ -988,7 +988,7 @@ export const RemoteServerFactory = {
                         if (typeof options.onSLASPrivateProxyRes === 'function') {
                             try {
                                 const customBuffer = options.onSLASPrivateProxyRes(
-                                    workingBuffer,
+                                    responseBuffer,
                                     proxyRes,
                                     req,
                                     res
diff --git a/packages/template-retail-react-app/CHANGELOG.md b/packages/template-retail-react-app/CHANGELOG.md
index 4cfc5663a8..1eefd4976d 100644
--- a/packages/template-retail-react-app/CHANGELOG.md
+++ b/packages/template-retail-react-app/CHANGELOG.md
@@ -2,7 +2,7 @@
 - [Bugfix] 1CC Bug Fixes [#3638](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3638)
 
 ## v9.0.0-preview.0 (Feb 06, 2026)
-- [Feature] One Click Checkout [#3552](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3552)
+- [Feature] One Click Checkout (in Developer Preview) [#3552](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3552)
 - [Feature] Add `fuzzyPathMatching` to reduce computational overhead of route generation at time of application load [#3530](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3530)
 - [Bugfix] Fix Passwordless Login landingPath, Reset Password landingPath, and Social Login redirectUri value in config not being used [#3560](https://github.com/SalesforceCommerceCloud/pwa-kit/pull/3560)
 - [Feature] PWA Integration with OMS
diff --git a/packages/template-retail-react-app/app/components/otp-auth/index.test.js b/packages/template-retail-react-app/app/components/otp-auth/index.test.js
index d238c89e33..330fb117c9 100644
--- a/packages/template-retail-react-app/app/components/otp-auth/index.test.js
+++ b/packages/template-retail-react-app/app/components/otp-auth/index.test.js
@@ -254,7 +254,6 @@ describe('OtpAuth', () => {
             })
             const mockVerify = jest.fn().mockReturnValue(verifyingPromise)
 
-            const user = userEvent.setup()
             renderWithProviders(
                 <OtpAuth
                     isOpen={true}
diff --git a/packages/template-retail-react-app/app/components/passwordless-login/index.jsx b/packages/template-retail-react-app/app/components/passwordless-login/index.jsx
index 28d8654452..32a44efa57 100644
--- a/packages/template-retail-react-app/app/components/passwordless-login/index.jsx
+++ b/packages/template-retail-react-app/app/components/passwordless-login/index.jsx
@@ -20,7 +20,7 @@ const PasswordlessLogin = ({
     handlePasswordlessLoginClick,
     isSocialEnabled = false,
     idps = [],
-    setLoginType = noop
+    setLoginType: _setLoginType = noop
 }) => {
     const [showPasswordView, setShowPasswordView] = useState(false)
 
diff --git a/packages/template-retail-react-app/app/pages/checkout-one-click/partials/one-click-contact-info.jsx b/packages/template-retail-react-app/app/pages/checkout-one-click/partials/one-click-contact-info.jsx
index 19fe7da189..ec2625420e 100644
--- a/packages/template-retail-react-app/app/pages/checkout-one-click/partials/one-click-contact-info.jsx
+++ b/packages/template-retail-react-app/app/pages/checkout-one-click/partials/one-click-contact-info.jsx
@@ -245,11 +245,19 @@ const ContactInfo = ({isSocialEnabled = false, idps = [], onRegisteredUserChoseG
                 lastEmailSentRef.current = normalizedEmail
                 return {isRegistered: true}
             } catch (error) {
-                const message = formatMessage(getAuthorizePasswordlessErrorMessage(error.message))
-                setError(message)
-                // Keep continue button visible if email is valid (for unregistered users)
-                if (isValidEmail(email)) {
+                // 404 = email not registered (guest); treat as guest and continue
+                const isGuestNotFound = String(error?.message || '').includes('404')
+                if (isGuestNotFound && isValidEmail(email)) {
+                    setError('')
                     setShowContinueButton(true)
+                } else {
+                    const message = formatMessage(
+                        getAuthorizePasswordlessErrorMessage(error.message)
+                    )
+                    setError(message)
+                    if (isValidEmail(email)) {
+                        setShowContinueButton(true)
+                    }
                 }
                 // Update the last email sent ref even on error to prevent retrying immediately
                 lastEmailSentRef.current = normalizedEmail
diff --git a/packages/template-retail-react-app/config/default.js b/packages/template-retail-react-app/config/default.js
index a00e2bb735..8ef0dfe5a0 100644
--- a/packages/template-retail-react-app/config/default.js
+++ b/packages/template-retail-react-app/config/default.js
@@ -74,6 +74,9 @@ module.exports = {
             appSourceId: '7ae070a6-f4ec-4def-a383-d9cacc3f20a1',
             tenantId: 'g82wgnrvm-ywk9dggrrw8mtggy.pc-rnd'
         },
+        // Note: this feature is in Developer Preview at this time. To use One Click Checkout,
+        // enable the oneClickCheckout flag and configure private SLAS client. For more details, please
+        // check https://github.com/SalesforceCommerceCloud/pwa-kit/releases/tag/v3.16.0
         oneClickCheckout: {
             enabled: false
         },